Bought my first set of radials in 1968. Since then, have purchased only 1 set of bias-ply tires - for a numbers matching show car.
Suggestion - if going radials, don't try to beat the price by ordering mail-order, or whats on sale. Talk to an older gentleman at a local tire shop, and see what they reccomend; then ask if these will be going on sale any time soon. Getting the tire correct for the application is important.
My own personal experience is that radials will give 15~40 percent better fuel economy, and outlast 3 to 5 sets of bias-ply tires. Others may have differing experiences.
Jon.